A relatively new analytical instrument for the measurement of BOD5, COD, TSS, TOC, nitrates and surfactants has been developed commercially. It is based on the use of ultraviolet spectrophotometry and a deterministic approach to analyze the sample’s spectrum by comparing it with a series of historical reference spectra. Using standard methods for the measurement of BOD5, TSS and TOC as true values, the use of this instrument was evaluated. The samples tested were obtained from both wastewater and water treatment facilities. Results indicate that the BOD5 measurement performed best. There was no correlation found for TSS or TOC.